This invention relates generally to transferring a fluid from one vial to another. More particularly, the invention is directed to transferring an aliquot of a fluid, such as blood, from one closed vial to another without exposing an operator to the fluid.
Automated blood and blood cell analyzers are well known. These analyzers typically utilize a portion of a whole or pre-prepared blood sample. When the blood sample is taken from a subject, it usually is placed into a vial or test tube. With the potential of exposure to highly infectious diseases by an operator, such as the HIV virus or hepatitis, the vial preferably is closed, typically by a resealable robber stopper. Many types of blood sample sampling devices have been developed, generally following the procedure of piercing the vial stopper to aspirate a portion or aliquot of the blood sample. The needle probe or cannula then is removed from the vial and the stopper reseals to maintain the remainder of the blood sample sealed in the vial.
For some operations, the blood sample is combined or mixed (prepared) with another fluid or reagent outside of the analyzer prior to being aspirated into the analyzer. If the vial is opened or handled for a transfer operation; the risk of exposure is greatly increased. The vials, typically made of glass can break, removing the stopper can result in aerosols, the contaminated stopper then must separately be disposed of and the risk of spillage also increases.
It therefore would be desirable to provide a method of transferring fluids between closed vials without exposing the operator to the fluids. Further, it would be desirable to transfer a precise desired volume of fluid between the vials.